There are many reasons for MPs to stay inside the Palace of Westminster when mealtimes come around, not least that the immediate vicinity of parliament is generally packed with tourists, and has food outlets that reflect this. But most importantly, if you can dine lavishly for less than a fiver, why bother?

The popular parliamentary Terrace restaurant remains closed for the recess, but a typical pre-summer menu featured spinach soup for 55p and steak, mushroom and ale pie for £2.90. At the St Stephen's Tavern pub across the road from the Commons – by no means expensive by central London standards – yesterday's offering of summer vegetable soup would set you back £2.95 and a plate of sausage and mash £6.95.

Go to one of the more upmarket restaurants nearby and the difference is still more stark. While MPs could enjoy a pea, pepper and parmesan risotto at the Terrace for a mere £1.90, at the Osteria dell'Angolo restaurant an admittedly more ambitious clam and cuttlefish ink version comes in at £13, nearly seven times as expensive. At Shepherd's, another nearby restaurant where the traditional British cooking has long drawn MPs, yesterday's set menu included the option of pea and mint soup followed by steak and kidney pie. While this would cost £3.45 at the Terrace, here it would be £31.

A few minutes' walk further away, outside the more modest Astral Cafe, taxi driver Mick, 48, had just spent £4.20 on a takeaway tea, roll and cake. He was perhaps predictably unimpressed to learn what this sum might have bought him in the Commons.

"It doesn't surprise me, but I don't see why we should subsidise their food. I work nights, and if I don't bring anything in with me, like today, I can easily spend £10 or £12. It all adds up."